Calibration Of Check And Safety Parameters - AERMEC NRA 2000 Manual Tecnico

CHECK PARAMETERS
NOTE
(1) = version Y
14. 1 T H E R M O M A G N E T I C
SWITCHES FANS
14.2 T H E R M O M A G N E T I C
SWITCHES COMPRESSORS
14.3 TRANSDUCERS
PRESSURE SWITCHES
KEY
PA High pressure switch
PB Low pressure switch
TRA High pressure transducer
TRB Low pressure transducer
All units are thoroughly tested in the
factory before shipping. Nonetheless,
it is always good practice to check all
control and safety systems after a
reasonable period of operation.
All the control operations must be
carried out by qualified personnel; the
wrong settings on the above devices
can cause serious damage to the unit.
14.3. 1 High pressure switch
The high pressure switch stops the
compressor (generating the relative
alarm) when the delivery pressure
exceeds the set value.
The control of its correct working can
be made by closing the air suction
on the exchanger (in cold mode) and,
keeping the high pressure gauge under
control, checking it intervenes upon
reaching the calibrated value.
CALIBRATION OF CHECK AND SAFETY
14
PARAMETERS
Cooling set point
Heating set point
Antifreeze intervention
Total differential
Autostart
2000 2250
n° Ventilatori 4+4 4+6
MTV 1 9 A 9 A
MTV 2 9 A 9 A
MTV 3 9 A 13 A
MTV 4 9 A 13 A
2000 2250
MTC1 53 A 53 A
MTC1A 53 A 53 A
MTC1B / /
MTC2 53 A 53 A
MTC2A 53 A 53 A
MTC2B / /
MTC3 53 A 57 A
MTC3A 53 A 57 A
MTC3B / /
MTC4 53 A 57 A
MTC4A 53 A 57 A
MTC4B / /
2000
PA a freddo 27
PA a caldo H 27
PB HL 20
TRA 27
TRB 1
WARNING
If the switch does not trip at the
calibrated value, stop the compressor
immediately and identify the cause.
Reset is manual and only enabled
once the pressure drops below the
differential value. (For the set and
differential values, see the technical
manual).
14.3.2 Low pressure switch
The low pressure switch stops the
compressor (generating the relative
alarm) when the suction pressure
drops below the set value. The control
of its correct working can be made
(after about 5 minutes of operation) by
slowly closing the tap on the liquid pipe
and, keeping the low pressure gauge
under control, checking it intervenes
upon reaching the calibrated value.
min. standard
4 / -6 (1) 7 / -6 (1)
°C
°C 35 48
-9 3
°C
3 5
°C
2500 2800 3000
6+6 6+6 6+6
13 A 13 A 13 A
13 A 13 A 13 A
13 A 13 A 13 A
13 A 13 A 13 A
2500 2800 3000
57 A 57 A 53 A
57 A 57 A 53 A
/ / 53 A
57 A 53 A 53 A
57 A 53 A 53 A
/ 53 A 53 A
57 A 57 A 53 A
57 A 57 A 53 A
/ / 53 A
57 A 53 A 53 A
57 A 53 A 53 A
/ 53 A 53 A
2250 2500 2800
27 27 27
27 27 27
20 20 20
27 27 27
1 1 1
WARNING
If the switch does not trip at the
calibrated value, stop the compressor
immediately and identify the cause.
Reset is manual and only enabled
once the pressure rises above the
differential value. (For the set and
differential values, see the technical
manual).
14. 1 .3 Anti-freeze control
The anti-freeze control, managed
by electronic regulation and by the
temperature probe at the evaporator
outlet, has the job of preventing the
formation of ice when the water
flow rate is too low. The control of
its correct working can be made by
gradually increasing the anti-freeze
set until it exceeds the outlet water
temperature and, keeping the water
max.
14
50
4
10
auto
3300 3600
8+8 8+8
17 A 17 A
17 A 17 A
17 A 17 A
17 A 17 A
3300 3600
53 A 57 A
53 A 57 A
53 A 57 A
57 A 57 A
57 A 57 A
57 A 57 A
53 A 57 A
53 A 57 A
53 A 57 A
57 A 57 A
57 A 57 A
57 A 57 A
3000 3300 3600
27 27 27
27 27 27
20 20 20
27 27 27
1 1 1
27